THERMO-ELASTIC DISSIPATION OF MICROBEAM RESONATORS IN THE FRAMEWORK OF GENERALIZED THERMO-ELASTICITY THEORY

摘要

Thermo-elastic dissipation of microbeam resonators is studied by the generalized thermo-elasticity theory of Lord and Shulman's model. Explicit formulae of thermo-elastic damping and frequency shift have been derived. Influences of the beam height and aspect ratio are examined. The thermal relaxation time is determined by Chester's formula, where the phonon velocity is replaced by the flexural wave velocity in the microbeam. Numerical results show that the discrepancy between results of the present non-Fourier theory and classical ones increase with decrease of aspect ratio of the beam resonator. For fixed aspect ratios thermo-elastic damping tends to increase from lower vibration modes to higher modes.